/*
 * Copyright (C) 2013 Square, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.squareup.okhttp;

import com.squareup.okhttp.internal.Platform;
import com.squareup.okhttp.internal.http.HttpMethod;

import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.HashMap;
import java.util.List;

/**
 * An HTTP request. Instances of this class are immutable if their {@link #body}
 * is null or itself immutable.
 */
public final class Request {
    private final String urlString;
    private final String method;
    private final Headers headers;
    private final RequestBody body;
    private final Object tag;

    private volatile URL url; // Lazily initialized.
    private volatile URI uri; // Lazily initialized.
    private volatile CacheControl cacheControl; // Lazily initialized.

    private Request(Builder builder) {
        this.urlString = builder.urlString;
        this.method = builder.method;
        this.headers = builder.headers.build();
        this.body = builder.body;
        this.tag = builder.tag != null ? builder.tag : this;
        this.url = builder.url;
    }

    public URL url() {
        try {
            URL result = url;
            return result != null ? result : (url = new URL(urlString));
        } catch (MalformedURLException e) {
            throw new RuntimeException("Malformed URL: " + urlString, e);
        }
    }

    public URI uri() throws IOException {
        try {
            URI result = uri;
            return result != null ? result : (uri = Platform.get().toUriLenient(url));
        } catch (URISyntaxException e) {
            throw new IOException(e.getMessage());
        }
    }

    public String urlString() {
        return urlString;
    }

    public String method() {
        return method;
    }

    public Headers headers() {
        return headers;
    }

    public String header(String name) {
        return headers.get(name);
    }

    public List<String> headers(String name) {
        return headers.values(name);
    }

    public RequestBody body() {
        return body;
    }

    public Object tag() {
        return tag;
    }

    public Builder newBuilder() {
        return new Builder(this);
    }

    /**
     * Returns the cache control directives for this response. This is never null,
     * even if this response contains no {@code Cache-Control} header.
     */
    public CacheControl cacheControl() {
        CacheControl result = cacheControl;
        return result != null ? result : (cacheControl = CacheControl.parse(headers));
    }

    public boolean isHttps() {
        return url().getProtocol().equals("https");
    }

    @Override
    public String toString() {
        return "Request{method="
                + method
                + ", url="
                + urlString
                + ", tag="
                + (tag != this ? tag : null)
                + '}';
    }

    public static class Builder {
        private String urlString;
        private URL url;
        private String method;
        private Headers.Builder headers;
        private RequestBody body;
        private Object tag;

        public Builder() {
            this.method = "GET";
            this.headers = new Headers.Builder();
        }

        private Builder(Request request) {
            this.urlString = request.urlString;
            this.url = request.url;
            this.method = request.method;
            this.body = request.body;
            this.tag = request.tag;
            this.headers = request.headers.newBuilder();
        }

        public Builder url(String url) {
            if (url == null) throw new IllegalArgumentException("url == null");
            urlString = url;
            return this;
        }

        public Builder url(URL url) {
            if (url == null) throw new IllegalArgumentException("url == null");
            this.url = url;
            this.urlString = url.toString();
            return this;
        }

        /**
         * Sets the header named {@code name} to {@code value}. If this request
         * already has any headers with that name, they are all replaced.
         */
        public Builder header(String name, String value) {
            headers.set(name, value);
            return this;
        }

        /**
         * Adds a header with {@code name} and {@code value}. Prefer this method for
         * multiply-valued headers like "Cookie".
         */
        public Builder addHeader(String name, String value) {
            headers.add(name, value);
            return this;
        }

        public Builder removeHeader(String name) {
            headers.removeAll(name);
            return this;
        }

        /**
         * Removes all headers on this builder and adds {@code headers}.
         */
        public Builder headers(Headers headers) {
            this.headers = headers.newBuilder();
            return this;
        }

        public Builder get() {
            return method("GET", null);
        }

        public Builder head() {
            return method("HEAD", null);
        }

        public Builder post(RequestBody body) {
            return method("POST", body);
        }

        public Builder delete() {
            return method("DELETE", null);
        }

        public Builder put(RequestBody body) {
            return method("PUT", body);
        }

        public Builder patch(RequestBody body) {
            return method("PATCH", body);
        }

        public Builder method(String method, RequestBody body) {
            if (method == null || method.length() == 0) {
                throw new IllegalArgumentException("method == null || method.length() == 0");
            }
            if (body != null && !HttpMethod.hasRequestBody(method)) {
                throw new IllegalArgumentException("method " + method + " must not have a request body.");
            }
            this.method = method;
            this.body = body;
            return this;
        }

        /**
         * Attaches {@code tag} to the request. It can be used later to cancel the
         * request. If the tag is unspecified or null, the request is canceled by
         * using the request itself as the tag.
         */
        public Builder tag(Object tag) {
            this.tag = tag;
            return this;
        }

        public Request build() {
            if (urlString == null) throw new IllegalStateException("url == null");
            return new Request(this);
        }

        /**
         * Setting requst headers
         *
         * @param heads
         * @return
         */
        public Builder setHeaders(HashMap<String, String> heads) {
            headers.addAll(heads);
            return this;
        }
    }
}
